Kelly-bar bushing



April 18, 1939. w. A. ABEGG KELLY-BAR BUSHING" Filed April 15, 1938 2 Sheets-Sheet l //VVfNTO/? WALTf/P A. A5566 ATTORNEY April 18, 1939. w A- ABEGG 2,155,109

KELLY-BAR BUSHING Filed April 13, 1938 2 Sheets-Sheet 2 lNVfNTOR WAZZ ff? A A5566 39 ATTORNEY Patented Apr. 18, 1939 UNITED STATES PATENT OFFICE KELLY-BAR BUSHING Walter A. Abegg, Los Angeles, Calif.

Application April 13, 1938, Serial No. 201,768

11 Claims.

This invention relates to well drilling equipment, and particularly pertains to a Kelly-bar bushing.

In well drilling operations it is the usual practice to lower a string of drill pipe and a cutter into the well through the rotary table and to attach a Kelly-bar to the upper end thereof. A Kelly-bar is usually of square cross-section and extends through a bushing in the rotary table which bushing has a square opening so that rotation of the rotary table may be transmitted to the Kelly-bar to provide driving rotation for the drill bit and the drill string. In View of the fact that the Kelly-bar is supported so that it may move vertically through the bushing, and for the additional reason that the drivin torque imparted to the Kelly-bar by the bushing will cause the Kelly-bar to wear, various expedients have been provided in an attempt to permit the Kelly-bar 0 to move through the bushing with a minimum amount of wear and binding, and to make it possible for the wear parts to be taken up or replaced. Heretofore in most instances the structures provided have been expensive to manufacture and to repair, and have also been of relatively delicate construction so that they have become broken easily. It is the principal object of the present invention therefore to provide a Kelly-bar bushing, the body of which is extremely strong and rugged and will not be damaged easily when handled at the drill rig, and which body is designed to receive and to eifectually hold guide inserts not liable to be easily damaged while presenting efficient guide and wear surfaces to the faces of the Kelly-bar, with no looseness or lost motion in the seat of the bushing body proper and with wear surfaces readily adapting themselves to the faces of the Kelly-bar. The structure also has the additional advantage that the inserts may be quickly interchanged to accommodate Kelly-bars of difierent sectional dimensions.

The invention contemplates the provision of a Kelly-bar bushing body adapted to seat within a rotary table and which body is formed with seat sections to receive guide inserts, the guide inserts being detachably secured in place by simple and positive fastening means.

The invention is illustrated by way of example in the accompanying drawings in which:

Figure 1 is a view in plan showing the Kellybar bushing with which the present invention is concerned, and indicating a Kelly-bar in cross section.

Fig. 2 is a view in vertical section showing the assembled Kelly-bar bushing mounted upon the Kelly-bar.

Fig. 3 is a view in side elevation showing one of the guide inserts.

Fig. 4 is a View in elevation showing one of the inserts edgewise.

Fig. 5 is a view in plan showing one of the inserts.

Fig. 6 is a view in plan showing another insert adapted to engage a Kelly-bar of smaller see tional dimension than would be engaged by the inserts shown in Fig. 5.

Referring more particularly to the drawings, l0 indicates the body of a Kelly-bar bowl of the construction with which the present invention is concerned. This body is formed with a substantially cylindrical main portion H extending vertically. The lower end of the main portion 1 i is downwardly and inwardly tapered as indicated at l2 in Fig. 2. Above the tapered portion is a squared collar 13 which fits within the usual squared seat of a well rig rotary table.

Ina

horizontal plane directly above the squared seat and disposed in equal spaced relation to each other around the main portion l of the body are horizontally extending guard lugs M which are substantially semi-circular in plan and at a point midway their circumferential length are formed with arcuate recesses l5.

Projecting upwardly from the plane of the guard lugs M is a tubular portion 16 of the body. The upper end of this tubular portion terminates in an outwardly projecting annular marginal flange l1, while at points around the body and lying within the vertical planes of the centers of the guard lugs I l and their recesses l5 downwardly and outwardly extending bosses l8 occur.

The bosses l8 terminate in flat faces l9 disposed at right angles to the longitudinal center of bolt openings 28,

one of which extends through each boss.

The

upper end faces of the bosses are formed with transverse inclined slots 2| which are longitudinally aligned with radial axes of the body portion These slots accommodate the hooked head 22 of clamping bolts 23. By reference to Fig. 2

of the drawings it will be seen that the hooked member I I.

The heads 22 are formed with an inclined back face 3|! which provides suitable clearance. The design and dimensions of the head 22 are such as to insure that when the bolts are in a clamping position the heads 22 will lie within the slotted grooves 2| of the boss and will be protected against blows which might be delivered to them by objects with which they may come in contact. The bolts are of a length designed to allow the bolts to clear the guard lugs l4 and to be thereabove when in a clamping position. Semi-circular recesses |5 of the guard lugs are provided for drilling clearance in the manufacture. Clamping nuts 3| are provided for the bolts. It is preferable that the nuts 3| be castellated to receive a locking cotter pin 32. Attention is directed to the fact that the portion of the bolt below the nut 3| when tightened is of reduced diameter so indicated at 24. This reduced diameter represents the thread depth so that the nut will screw off the thread and also to insure that the thread will not be uncovered and damaged to prevent the unscrewing of the nut. A cotter pin 32' prevents accidental removal and loss of the nut.

The bolts are designed to grip and hold in position guide inserts 33. These inserts provide the wear surface which intimately contacts the longitudinal side faces of the Kelly-bar 34. The wear faces of the inserts 33 are preferably slightly convexed longitudinally as indicated at 35 so that binding due to a slight mis-alignment or deviation from the perpendicular of the Kelly-bar will not occur. The back faces of the inserts are flat as indicated at 36, while the opposite edges 31 are at right angles to the flat back face. The

' inserts vertically slide into position within the grooves 26. -It is preferable that the horizontal width of the grooves 26 and the horizontal thickness of the inserts 33 will be such as to insure that the contiguous vertical edges of the side faces of the inserts will substantially coincide and that the body portions of the inserts will thus be arranged at right angles to each other to define an opening of square section through which the Kelly-bar 34 passes. The maximum opening through a given Kelly-bar bushing of the type here shown would be obtained by the use of inserts as shown in Figs. 3 and 4 of the drawings where the transverse planes of the inserts would substantially intersect at the forward edges of the side faces of the inserts as shown in Fig. 1. Variations of this arrangement to accommodate Kelly-bars of smaller dimension would be taken care of by inserts formed as shown in Fig. 6 of the drawings where the thickness of the inserts is increased to reduce the size of the opening and where the opposite sides of the insert are beveled at 45 as indicated at 38 in Fig. 6, so that a reduced wear face 35' would be provided in exceeding the width of the fiat face of the Kelly-bar with which it is used. In order to hold the inserts in position without the necessity of expensive machine work in forming dovetailed grooves along the sides 31 of the inserts and the vertical seats the body of the inserts are substantially rectangular in section throughout the major portion of their length and terminate in lower ends having an arcuately curved outer face 39 undercut in the back face 36. This arcuately curved outer face fits within an annular seat 40-which is turned in the lower end of the passageway 21 through the body member l0 and which seat terminates in a V-shaped groove 4|. The groove 4| receives a tapered toe 42 which interlocks therewith to prevent lateral movement of the head 22 of the bolt 24.

lower end of the inserts. An annular groove 43 is formed around the wall of the central opening 2'! in the body and above the annular seat 40 to facilitate in machining. The face 35 of the insert has a curved upper and lower portion 44 which reduces the thickness of the inserts and facilitates in the movement of the Kelly-bar 34 therethrough as well as in the insertion of the inserts 33 while the Kelly-bar is in place. The upper ends of the inserts 33 are formed with a vertical groove 45 which is disposed centrally of the width of the inserts. The vertical grooves 45 terminate in an inclined bottom face 46 which extends inwardly and downwardly across the insert at the same inclination as the face 25 of the The upper edge of the inclined face 46 lies in a plane above the plane of the bottom face 41 of the groove 2| which is cut in the boss l8. Thus the head 22 of the bolts 24 will hook over the upper edges of the face 46 and will hold the inserts down in their seated position within the grooves 45 and with the toes 42 of the inserts firmly held in the V-shaped seats 4| at the bottom of the annular seat 40. It is to be understood that the heads 22 of the bolts 24 have opposite flat faces which are disposed between side faces of the grooves 45 so that the head cannot rotate when in position. In order to facilitate removal and insertion of the bolts 24 into the openings 2!] through the bosses l8 one side face of each of the grooves 45 is relieved with an inclined cutaway portion 41. This makes it possible to gradually rotate the head 22 as the nut 3| is unscrewed so that the head may be re tracted from the face of the Kelly-bar, thus insuring that the bolt may be removed or placed in.

position without interference with the Kelly-bar when the Kelly-bar is in place.

In operation of the present invention the body structure It), including the bowl I is constructed as here shown. In some instances, however, if desired the guard lugs |4 may be eliminated. The bowl II is machined to form the annular seat 40 and the vertical seat grooves 26. The bolts 24 are inserted through their openings 20 with their heads turned away from the faces of the Kelly-bar as indicated by dotted lines in Fig. 2 of the drawings. A Kelly-bar may be inserted through the body member and the body member may be mounted within the portion of a rotary table designed to receive it without obstruction by the bolts. When the Kelly-bar has been extended through the body member the inserts 33 may be lowered in position along the flat faces of the Kelly-bar 34 until their toe portions 42 seat within the Vshaped grooves 4| and at which time the body of the inserts 33 will be properly seated within the vertical seats 26 formed to receive them. The heads 24 of the bolts may be rotated to positions overhanging the upper ends of the inserts. The nut 3| at the lower ends of the bolts may then be screwed up until the head begins to tighten, after which the head may be drawn down the inclined face 41 of the groove 45 and may be rotated as it moves downwardly to a position in register with the groove, at which 34 and will make it possible for the insert to properly contact therewith while permitting the Kelly-bar to reciprocate through the bushing structure without binding or excessive wear. It will be understood that when the maximum size to be accommodated, special inserts for a particular sized Kelly-bar may be provided, as shown in Fig. 6 of the drawings. By the use of these inserts a contracted square opening will be formed, the dimensions of which will appropriately agree with the squared section of the Kellybar.

It is to be understood that while the inserts 33 are here shown as provided one for each Kellybar face it might be desirable to apply them to a lesser number of only or that one insert might engage more than one face. It is also within the contemplation of this invention to install inserts permanently and to form them with or without the convex wear faces.

It will thus be seen that by the construction here disclosed, a rugged Kelly-bar bushing will be provided,.having strong clamping means which are not liable to be damaged in normal drilling operations, and which bushing is further provided with guide inserts each made of a single piece of material selected for its strength and wear resisting qualities, and designed so that it may be easily placed in position or removed therefrom.

While I have shown the preferred form of my invention, as now known to me, it will be understood that various changes might be made in the combination, construction, and arrangement of parts, by those skilled in the art, without departing from the spirit of the invention as claimed.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. A Kelly-bar bushing comprising a bodymember engaging a rotary table on which it is placed, a bowl formed as a part of said body member and extending upwardly therefrom and being formed with an opening therethrough, longitudinal slots formed in the wall of said opening, the number of slots agreeing with the side faces of a Kelly-bar, guide inserts adapted to be vertically aligned, one in each of said longitudinal grooves, the innermost faces of said inserts bearing against the vertical faces of the Kelly-bar, interlocking means between the lower ends of the guide inserts and body member to limit downward movement of the inserts and to hold the lower ends of the inserts against lateral movement within the grooves, inclined bosses formed as a part of the body member and formed around the bowl adjacent to the grooves therein, and hook bolts disposed in said bosses with their heads overhanging the grooves and engaging faces at the upper ends of the guide inserts, whereby to hold the guide inserts in their interlocking position when the bolts are positioned in their bosses and tightened.

2. A Kelly-bar bushing comprising a substantially tubular body member adapted to be operatively positioned with relation to a rotary table, longitudinal seats formed in the inner wall of said tubular body member, said seats being characterized as having opposite fiat side walls disposed parallel to each other and parallel to an intermediate radial center line and a flat back wall at right angles thereto, a transverse groove at the lower end of said seat, a guide insert fitting into the seat and having greater thickness than the depth of the seat whereby a guide face will be presented to the side of a Kelly-bar extending through the body member, a boss formed in connection with the body member and having an opening therethrough inclined downwardly and outwardly, a hooked bolt extending through said opening and having an overhanging hook end engaging an upper face of the guide insert, the lower end of the guide insert engaging the interlocking means whereby the hook bolt will hold the guide insert within the seat.

3. A Kelly-bar bushing comprising a tubular bowl through which a Kelly-bar extends, a plurality of longitudinally extending seats formed in the inner face of the wall of the bowl, said seats being substantially rectangular in cross-section and extending downwardly from the mouth of the bowl to a point adjacent the lower end thereof, an undercut annular seat being formed at the lower ends of said seats and having a diameter tangent to the back wall of the bowl and terminating in a V-shaped groove, a relatively flat guide insert of substantially rectangular section, one of which fits within each of said seats and terminates at its lower end in a portion of arcuate section fitting into the annular seat portion and the V-shaped recess, the upper end of the insert terminating substantially in the plane of the mouth of the bowl, a slotted recess formed in the upper end of the bowl and terminating in a downwardly and inwardly inclined bottom face, a set of bolt bosses carried by the bowl, one disposed along the plane of the radial center line of each of the seats and being inclined downwardly and outwardly, and a set of bolts, one for each of said bosses, said bolts being formed with an overhanging head portion having a gripping face disposed v in a plane at right angles to the longitudinal axis of the bolt and coinciding with and exerting pressure against the inclined bottom face of the groove within its seat.

4. A Kelly-bar bushing comprising a tubular bowl through which a Kelly-bar extends, a plurality of longitudinally extending seats formed in the inner face of the wall of the bowl, said seats being substantially rectangular in cross-section and extending downwardly from the mouth of the bowl to a point adjacent the lower end thereof, an undercut annular seat being formed at the lower ends of said seats and having a diameter tangent to the back wall of the bowl and terminating in a V-shaped groove, a relatively flat guide insert of substantially rectangular section, one of which fits within each of said seats and terminates at its lower end in a portion of arcuate section fitting into the annular seat portion and the V- shaped recess, the upper end of the insert terminating substantially in the plane of the mouth of the bowl, a slotted recess formed in the upper end of the bowl and terminating in a downwardly and inwardly inclined bottom face, a set of bolt bosses carried by the bowl, one disposed along the plane of the radial center line of each of the seats and being inclined downwardly and outwardly, and a set of bolts, one for each of said bosses, said bolts being formed with an overhanging head portion having a gripping face disposed in a plane at right angles to the longitudinal axis of the bolt and coinciding with and exerting pressure against the inclined bottom face of the groove within its seat, the head of said bolt overhanging one side of its shank only and being formed to fit between the side walls of the groove in the upper end of the insert.

5. A Kelly-bar bushing comprising a tubular bowl through which a Kelly-bar extends, a plurality of longitudinally extending seats formed in the'inner face of the wall of the bowl, said seats being substantially rectangular in cross-section and extending downwardly from the mouth of the bowl to apoint adjacent the lower end thereof, an undercut annular seat being formed at the lower ends of said seats and having a diameter tangent to the back wall of the bowl and terminating in a V-shaped groove, a relatively fiat guide insert of substantially rectangular section, one of which fits within each of said seats and terminates at its lower end in a portion of arcuate section fitting into the annular seat portion and the V-shaped recess, the upper end of the insert terminating substantially in the plane of the mouth of the bowl, a slotted recess formed in the upper end of the bowl and terminating in a downwardly and inwardly inclined bottom face, a set of bolt bosses carried by the bowl, one disposed along the plane of the radial center line of each of the seats and being inclined downwardly and outwardly, and a set of bolts one for each of said bosses, said bolts being formed with an overhanging head portion having a gripping face disposed in a plane at right angles to the longitudinal axis of the bolt and coinciding with and exerting pressure against the inclined bottom face of the groove within its seat, the head of said bolt overhanging one side of its shank only and being formed to fit between the side walls of the groove in the upper end of the insert, the overhanging end face of said head lying parallel to the vertical face of the Kelly-bar and spaced therefrom.

6. A Kelly-bar bushing comprising a tubular bowl through which a Kelly-bar extends, a plurality of longitudinally extending seats formed in the inner face of the wall of the bowl, said seats being substantially rectangular in crosssection and extending downwardly from the mouth of the bowl to a point adjacent the lower end thereof, an undercut annular seat being formed at the lower ends of said seats and having a diameter tangent to the back wall of the bowl and terminating in a V-shaped groove, a relatively flat guide insert of substantially rectangular section, one of which fits within each of said seats and terminates at its lower end in a portion of arcuate section fitting into the annular seat portion and the V-shaped recess, the upper end of the insert terminating substantially in the plane of the mouth of the bowl, a slotted recess formed in the upper end of the bowl and terminating in a downwardly and inwardly inclined bottom face, a set of bolt bosses carried by the bowl, one disposed along the plane of the radial center line of each of the seats and being inclined downwardly and outwardly, and a set of bolts one for each of said bosses, said bolts being formed with an overhanging head portion having a gripping face disposed in a plane at right angles to the longitudinal axis of the bolt and coinciding with and exerting pressure against the inclined bottom face of the groove within its seat, the head of said bolt overhanging one side of its shank only and being formed to fit between the side walls of the groove in the upper end of the insert, the overhanging section and extending downwardly from the mouth of the bowl to a point adjacent the lower end thereof, an undercut annular seat being formed at the lower ends of said seats and having a diameter tangent to the back wall of the bowl and terminating in a V-shaped groove, a relatively flat guide insert of substantially rectangular section, one of which fits within each of said seats and terminates at its lower end in a portion of arcuate section fitting into the annular seat portion and the V-shaped recess, the

upper end of the insert terminating substantiallyin the plane of the mouth of the bowl, a slotted recess formed in the upper end of the bowl and terminating in a downwardly and inwardly inclined bottom face, a set of bolt bosses carried by the bowl, one disposed along the plane of the radial center line of each of the seats and being inclined downwardly and outwardly, and a set of bolts disposed in a plane at right angles to the longitudinal axis of the bolt and coinciding with and exerting pressure against the inclined bottom face of the groove within its seat, the head of said bolt overhanging one side of its shank only and being formed to fit between the side walls of the groove in the upper end of the insert, the overhanging end face of said head lying parallel to the vertical face of the Kelly-bar and spaced therefrom, with the upper end of the head lying in a plane parallel to the mouth of the bowl, the back of the head being inclined with relation to the longitudinal axis of the bolt.

8. A Kelly-bar bushing comprising a tubular bowl through which a Kelly-bar extends, a plurality of longitudinally extending seats formed in the inner face of the wall of the bowl, said seats being substantially rectangular in crosssection and extending downwardly from the mouth of the bowl to a point adjacent the lower end thereof, an undercut annular seat being formed at the lower ends of said seats and having a diameter tangent to the back wall of the bowl and terminating in a V-shaped groove, a relatively flat guide insert of substantially rectangular section, one of which fits within each of said seats and terminates at its lower end in a portion of arcuate section fitting into the annular seat portion and the V-shaped recess, the upper end of the insert terminating substantially in the plane of the mouth of the bowl, a slotted recess formed in the upper end of the bowl and terminating in a downwardly and inwardly inclined bottom face, a set of bolt bosses carried by the bowl, one disposed along the plane of the radial center line of each of the seats and being inclined downwardly and outwardly, and a set of bolts, one for each of said bosses, said bolts being formed with an overhanging head portion having a gripping face disposed in a plane at right angles to the longitudinal-axis of the bolt and coinciding with and exerting pressure against the inclined bottom face of the groove within its seat, one side wall. of the groove in the insert being upwardly and outwardly tapered whereby the head may be rotated upwardly and out of the groove and away from the Kelly-bar as the nut of the bolt is loosened.

9. A Kelly-bar bushing comprising a tubular bowl, guide seat inserts formed longitudinally along the inner face of the bowl, said guide seats being substantially rectangular in shape and having a vertical back wall and parallel side walls, the seats agreeing in number with the side faces of a Kelly-bar extending through the bowl, said seats terminating at their lower end in an annular wall section concentric with the bowl, the circumference of which is tangent to the back face of the seats and which annular portion terminates in a shoulder forming an upwardly presented V-shaped annular groove, a plurality of bosses formed around the mouth of the bowl and as a part of the bowl, said bosses having a bolt opening therethrough, the longitudinal axis of which extends downwardly and outwardly and lies in a plane coincident with the median center line of a complementary insert seat, the upper end of the bolt opening intersecting the seat at a point below its upper end, a plurality of guide inserts substantially rectangular in section seated within the several guide insert seats and having a toe portion interlocking within the V-shaped groove at the bottom of the guide insert seats, a recess formed in the upper edge of each of the guide inserts and having opposite parallel side walls and a downwardly and inwardly inclined bottom face, bolts, one for each of said bosses, a head overhanging one side of each of said bolts and fitting in the a recess of a complementary guide insert, said head being formed with a face coinciding with the inclined face of said recess, and a nut for each bolt to draw the bolt down in a clamping position.

10. A Kelly-bar bushing comprising a tubular bowl, guide seat inserts formed longitudinally along the inner face of the bowl, said guide seats being substantially rectangular in shape and having a vertical back wall and parallel side walls, the seats agreeing in number with the side faces of a Kelly-bar extending through the bowl, said seats terminating at their lower end in an annular wall section concentric with the bowl, the circumference of which is tangent to the back face of the seats and which annular portion terminates in a shoulder forming an upwardly presented V-shaped annular groove, a plurality of bosses formedaround the mouth of the bowl and as a part of the bowl, said bosses having a bolt opening therethrough, the longitudinal axis of which extends downwardly and outwardly and lies in a plane coincident with the median center line of a complementary insert seat, the upper end of the bolt opening intersecting the seat at a point below its upper end, a plurality of guide inserts substantially rectangular in section seated within the several guide insert seats and having a toe portion interlocking within the V-shaped groove at the bottom of the guide insert seats, a recess formed in the upper edge of each of the guide inserts and having opposite parallel side walls and a downwardly and inwardly inclined bottom face, bolts, one for each of said bosses, a head overhanging one side of each of said bolts and fitting in the recess of a complementary guide insert, said head being formed with a face coinciding with the inclined face of said recess, and a nut for each bolt to draw the bolt down in a clamping position, said inserts having their outer faces convexed longitudinally and contacting with the side faces of the Kelly-bar.

11. A Kelly-bar bushing comprising a body portion adapted to engage the rotary table of a well drilling rig, a bowl formed as a part thereof and having a relatively square passageway therethrough to accommodate a Kelly-bar, longitudinal extending seats, one in each face of the passageway through the bowl, guide inserts, one being disposed within each of said seats and extending longitudinally thereof, each of said inserts being substantially rectangular in horizontal cross section and extending substantially the width of the face of the Kelly-bar with which it contacts, said contacting face being flat horizontally and longitudinally tapered vertically from a transverse median line whereby there will be surface contact between the insert and the face of the bushing throughout the width of the face of the insert and the face of the bushing, and complete surface contact between the surface of the bushing and a vertically inclined face of an insert when the Kelly-bar assumes a position of vertical misalignment in angularity with that of the vertical taper of the faces.

WALTER A. ABEGG. 

